The detection of gas bubbles in a fluid is necessary in several fields and applications. In dialysis, gas bubbles must be removed prior to contacting dialysate with the blood of a patient across a semi-permeable membrane. In fuel lines or hydraulic lines, gas bubbles can damage or decrease efficiency of automobiles or machinery. However, known systems and methods for gas detection require passing a fluid through a fluid tube and determining the presence of bubbles digitally, or physical observation of a fluid line and making a determination as to whether gas bubbles are present. Known systems fail to provide an automated, accurate, and efficient method of determining both the presence of, and size of, gas bubbles in a fluid. Hence, there is a need for a gas bubble detector that can accurately and automatically determine whether gas bubbles exist in a fluid using a gas bubble detection algorithm with minimal human involvement. There is further a need for a gas bubble detector that can accurately determine the presence of gas bubbles of any size, and quantify the size of any gas bubbles detected.